In the past the Navy has found that there is a real need to gun launch a projectile with a fuze affixed to the forward end in a manner so as to recover the undamaged fuze.
In the past the recovery of fuzes that are affixed to the external forward end of projectiles has been impossible where low gun elevation angles are used.
Although a single stage parachute recovery system was developed in the early 1960s, such a system cannot be used at gun elevation below 19 degrees.
In present day testing of fuzes it is often times necessary to fire a test round at targets mounted within a few hundred feet of the ground. The recovery of the undamaged frontally mounted fuze for test purposes depends upon the efficiency of the recovery system. If the fuze impacts the ground at a high velocity it will be destroyed thereby making further tests or analysis impossible. In such a case the prior condition of the fuze cannot be analyzed and no determination can be made as to the cause of a failure of a fuze to properly detect the target. When a fuze is allowed to impact the earth at a high velocity the fuze is destroyed. It is obviously advantageous to recover the undamaged fuze so that analysis is possible.
In many situations the Navy has need to test and determine the conditions of fleet issued ammunition fuzes, particularly in a quantity of fuzed ammunition projectiles where there has been a fatal or near fatal malfunction.
For example, if a projectile explodes in a gun barrel or shortly after muzzle exit all fuzes and projectiles in the suspected lot may be declared unfit for use. In such a case it is obviously advantageous to test the fuzes under ordinary firing conditions without incurring further risk to personnel. In such cases the recovery of the fuze is critical to the test procedure. If the test exonorates the fuze the lot of fuzes may be used at great saving of re-procurement cost to the Government.
In another situation the recovery of fuzes on rounds or projectiles fired for test purposes saves a great deal of time in doing research and development. Without a means to recover fuzes after test firing the alternative test procedures in the laboratory are very time consuming. In addition, the laboratory testing of fuzes is not nearly so satisfactory as in gun launched testing after conventional firing.
When a failure of a projectile occurs at sea, the suspected rounds have to be shipped to a test facility for testing to determine the cause of failure. While live rounds are not used for testing, the gun-launched testing of fuzes with the recovery system of the instant invention represents such a great savings in time. The cycle time from failure of rounds in a distant field position to shipment of the suspected rounds with fuzes to a test facility, followed by analysis and testing and return of the rounds to the field when the present invention is used, is reduced from a few months to a matter of weeks or days. In short, the recycle testing time of fuzes is greatly reduced by use of the present invention.
Thus, it is also readily apparent that the Navy has great need to have a reliable system for fuze recovery.
The two stage parachute recovery system of the disclosed invention is such a system.
This two stage parachute recovery system solves a long standing problem for the Navy. In addition it saves both time and expense in research and development of experimental fuzes.